Just came along few same questions in my email regarding iPod touch Wi-Fi Grayed out bar or No Wi-Fi (Wireless) at all. Well I do feel your pain, because it happened to mine not too long ago. After 5 minutes of research I found this to be helpful, at least in my situation was
- Go To Settings
- Click on Safari
- Go bit down and click Clear Cache, Clear Cookies, Clear History
- Hold the Top (sleep/awake) button until you get red bar to swipe it
- Swipe the red bar to the left (iPod Touch should now turn off)
- Then Hold the Top (Sleep/Awake) button until you see Apple logo
- Wait until front screen displays
- See if that fixed it.
In most cases, this will do the trick. Another suggestion for you I have is to, reset the iPod Touch you can do it many ways, one way is to do it from the Settings and another one is via iTunes.
Hope this helps, do let me know in commenting section below.